1. Field of Invention
This invention relates to systems and methods for communication between a host computer and one or more client computers.
2. Description of Related Art
Many companies make significant investment in information technology, including computer hardware and the software that runs it. The architecture for the computer hardware is often a host computer in communication with a plurality of client computers. Often the host computer is a large complicated mainframe system, which is based on a character user interface (“CUI”) as opposed to a graphical user interface or (“GUI”). A typical approach for providing input to the host is to create a front end computer system, one in which the client appears to the host to be a human who is inputting commands at a keyboard. The more difficult part of the communication between the host and the client is how the host's response to the input is to be understood by the client.
In the airline industry, for example, each airline may own and operate its own host in accordance with the host's own syntax and protocols. The host may be used in communication with a variety of clients, where the clients are operated directly by customers or by booking agents. Each of the clients may submit commands to the host, and receive responses from the host via a host response screen. The responses from the host are then displayed by the particular client for its users. The difficult part is interpretation of the data presented in the host response screen and the formatting of this data for use by the client.
The traditional approach to interpretation of the data presented in the host response screen is to use a technique called “screen scraping”. During application development, a developer is given the layout of the host response screen that is to be interpreted. This layout includes details such as the length of data fields, how many occurrences of a field can be present, and what the coordinates of each field are (e.g., line and column positions), etc. A parser is developed which “scrapes” the data from the host response screen according to the prescribed layout, and formats the data for use by the application. The application then receives the formatted data, and performs further manipulations with the data.